Field of the Invention
The present invention relates to semiconductor measurement techniques, and more specifically to methods for detecting the presence of, and for measuring the magnitude of, mobile ions contained in the oxide layers of an integrated circuit.
Description of Related Art
Currently MOS capacitors and MOS transistors are used to detect mobile ions in insulating layers of semiconductor devices. The most common electrical methods are Bias-Temperature Capacitance-Voltage (BTCV), Bias-Temperature Current-Voltage (BT-IV), Triangular Voltage Sweep (TVS), and Thermally Stimulated Ionic Conductivity (TSIC), which are discussed in Instabilities in Silicon Devices, Silicon Passivation and Related Instabilities, Volume 1, Chapter 8, pp. 404-439, edited by G. Barbottin and A. Vapaille, copyright 1986. The common feature of all these methods is the ability to detect mobile ions either between the electrodes of capacitors or between the gate and substrate of MOS transistors.